rough idling, poor acceleration, misfiing............;

[jacquesd]

Hello,
on 04 28 2014 i entered a message, about the folowing problem on my 2008 with 15000 km

I noticed irregular idling, very bad acceleration between 2000 and 4500 rpm , with misfiring and sometimes running on 1 cylinder. high rpm seemed to run Ok
had a dealer visit, but on the pc, all data seemed to be ok and no failures were indicated.
we did the following steps WITHOUT ANY PROGRES
changed spark plugs
changed spark plug wires
changed O2 sensor
changed fuel filter
checked for cracs in pressure regulator lines
checked the canister for failures.

thanks to my dealer, who borrowed the necessary tools

checked the compression on both cylinders ( Ok)
checket the fuel pressure in the fuel pump.

Still no trace of the cause of the problem

I thought the bike was too rich, because of a clogged air filter, or a badly mounted air filter cover ( which i had taken away before).

Started the bike without the air filter cover and SURPRISE...............small flames in both trottle bodies!!!!!!!!!!!!!
was afraid there was something wrong with the ignition parts.

A freind of mine proposed to check the fuel injectors, he had the necessary tools at his working place. Injectors are easy to
take away. I was suspicious about this, but once you are that far any suggustion is welcome

They checked the injectors and they were OK.

Cleaned them with brake cleaner.

We put them back, without much hope.

We started bike and surprise............ the problem seemed to be solved!!!!!!!!!!!!!!!!!!and no more flames in trottle bodies , good
acceleration...........;

I' still touching wood, but after a short test drive, it remains OK
Hope my expierince can be usefull for other people having this mysterious failure.

grts

jacques

 

[AbNormy]

Dirty injectors?

Sent from my HTCONE using Tapatalk

 

[Chupaca]

Interesting..!!

dirty injectors at 15,000 miles..?? Does seem strange, what fuel and or additives are you using..??. I would still check vaccum lines. You may have moved something else while checking the injectors. But hey if it is running well keep an eye on things...be safe...hyea:

 

[MikeinGA]

Hello,
on 04 28 2014 i entered a message, about the folowing problem on my 2008 with 15000 km

I noticed irregular idling, very bad acceleration between 2000 and 4500 rpm , with misfiring and sometimes running on 1 cylinder. high rpm seemed to run Ok
had a dealer visit, but on the pc, all data seemed to be ok and no failures were indicated.
we did the following steps WITHOUT ANY PROGRES
changed spark plugs
changed spark plug wires
changed O2 sensor
changed fuel filter
checked for cracs in pressure regulator lines
checked the canister for failures.

thanks to my dealer, who borrowed the necessary tools

checked the compression on both cylinders ( Ok)
checket the fuel pressure in the fuel pump.

Still no trace of the cause of the problem

I thought the bike was too rich, because of a clogged air filter, or a badly mounted air filter cover ( which i had taken away before).

Started the bike without the air filter cover and SURPRISE...............small flames in both trottle bodies!!!!!!!!!!!!!
was afraid there was something wrong with the ignition parts.

A freind of mine proposed to check the fuel injectors, he had the necessary tools at his working place. Injectors are easy to
take away. I was suspicious about this, but once you are that far any suggustion is welcome

They checked the injectors and they were OK.

Cleaned them with brake cleaner.

We put them back, without much hope.

We started bike and surprise............ the problem seemed to be solved!!!!!!!!!!!!!!!!!!and no more flames in trottle bodies , good
acceleration...........;

I' still touching wood, but after a short test drive, it remains OK
Hope my expierince can be usefull for other people having this mysterious failure.

grts

jacques

I had the same problem with my 2011 RS-S SE5, it turned out to be a bad map sensor that only a few minutes to change.



Mike

 

[ChasingWind]

2008 symptom rough cutting out in lower rpm's but good higher rpm's above 4500 so far fixes have been
Delete Vapor canister and plug sensor
Bad map sensor
Plugs and wires
Clogged injectors

All great info thanks for updating your fix

 

[Bob Denman]

On a bike of that age with so few miles; could this have been caused by the fuel starting to, "turn to mush", in the system? :dontknow: